150,000 = a hundred and fifty thousand (you may say "one hundred") 200,000 = two hundred thousand 375,000 = three hundred and seventy-five thousand I'm not sure why you want to start "abbreviating" your English when you're still at a low level. Why shoot yourself in the foot? Anyway, "thousand" does have a few short forms, but remember these are slangy. You are far better off learning to say "thousand" properly and accepting that. At least know that these forms exist. K - as Kraut9 explained, K is short for "kilo". However, K can also mean kilometres and kilograms. Grand - if you're saying "grand", you may as well put "bucks" in your conversation as well. Thou - short for "thousand", obviously. Pay attention to the pronunciation. If you are obviously talking in units of thousands, then "thousand" may be dropped. Still it's very rare that you would need to do this.

(one) hundred fifty thousand two hundred thousand, three hundred seventy-five thousand With technical people you could replace 1000 with 'K' = hundred fifty K

The short way would be 150 thousand, 200 thousand, and 375 thousand, respectively.